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Intensive Outpatient Treatment (IOP) of Behavioral Health (BH) Problems: Engagement Factors Predicting Subsequent Service Utilization

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The purpose of the study is to 1) better understand patterns of utilization of Intensive Outpatient Treatment (IOP) Programs and Services in the State of Connecticut by adult Medicaid recipients experiencing a serious mental illness, substance use disorder, or co-occurring disorders; and 2) to determine the relationship between the duration of an IOP episode and connection to care rates for higher (i.e., rehospitalization) or lower levels of care following discharge. We hypothesized that the duration of an IOP episode would impact positively in reducing the use of higher levels of care while increasing the use of lower levels of care. In order to examine the frequency and duration of use of Intensive Outpatient (IOP) services by the CT Medicaid population, a two-year timeframe was selected: July 1, 2012 to June 30, 2014. A survival analysis was conducted to assess the risk of readmission to an IOP within 180 days based on demographic and utilization factors including, Age (in years on date of discharge), Race and Ethnicity, Gender, Homeless Status (at least one day in CY 2013), and Engagement Group (Intent to Treat, Early Termination, Minimally Adequate Dosage, & Target or More). To better understand the patterns of utilization associated with Adult IOP services, the average length of stay, number of treatment days, and average number of treatment days per week were explored. The number of unique individuals who were part of this analysis is 11,473, of which 2050 were mental health IOP utilizers (18%), 4598 were co-occurring IOP utilizers (40%), and 4825 (42%) were substance use IOP utilizers. For the total population, the average length of stay (ALOS) in days was 42 and the average number of treatment days attended per week was 2.5, for an average of 15 treatment days per episode of care. Among the IOP Cohorts, the Mental Health Cohort had the longest ALOS at 44.15 days, an average of 2.34 days of service per week, for an average of 14.76 days of IOP service per episode of care. The Substance Use Cohort had the shortest ALOS at 41.33 days, but had the highest intensity of services per week at 2.71 for an average of 16 days of service per episode of care. The Co-Occurring Cohort presented an ALOS of 41.74 days, an average of 2.32 services per week and an average of 13.83 sessions per episode. Overall there is evidence supporting an association between the number of days of care and protection from hospitalization, up to a certain number of days of care or number of days in IOP. Above the Minimally Adequate Dosage, the IOP protection factor seems to reach a plateau. This means that after 16 days of care, the chances of hospitalization remain the same regardless of the additional days provided.

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“This work was funded in part by the State of Connecticut, Behavioral Health Partnership partner agencies, which includes The Department of Social Services, The Department of Children and Families, and the Department of Mental Health and Addiction Services. This publication does not express the views of these partner agencies or the State of Connecticut. The views and opinions expressed are those of the authors.”

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Correspondence to Mark Costa.

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Costa, M., Plant, R.W., Feyerharm, R. et al. Intensive Outpatient Treatment (IOP) of Behavioral Health (BH) Problems: Engagement Factors Predicting Subsequent Service Utilization. Psychiatr Q 91, 533–545 (2020).

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